热强化气相抽提在典型有机污染场地修复中的应用

Application of thermal enhanced vapor extraction in remediation of typical organic pollutants contaminated site

阐述了原位燃气热脱附技术在北方某典型焦化厂重污染地块修复中的实际工程应用,对工艺设计、设备配置、加热井布置和加热运行策略进行了详述,分析了修复后特征污染物苯和苯并(a)芘的去除削减情况,同时描述了不同深度土壤的升温状况。结果表明,经过55 d的原位加热后,修复地块达到了预期设计的目标温度350℃,修复后土壤中2种特征污染物苯并(a)芘和苯的含量分别低于0.50和0.92 mg/kg,其去除率皆>99%,满足修复目标要求。原位燃气热脱附技术表现出的加热快、污染物去除效果好、无二次污染以及不涉及土壤开挖、转运等诸多优势使其具有良好的发展和应用前景。

The engineering application of in situ gas thermal desorption(ISTD)in the remediation process of a typical site contaminated seriously by organic pollutants in a coking plant was described,including the process design,device configuration,layout of heating well and the heating strategy.The removal performances of benzene and benzo(a)pyrene and the temperature rising status were analyzed after remediation.The results showed the target temperature(350℃)of the site reached the expected design after the heating for 55 days.The total removal rate was more than 99%for benzene(less than 0.50 mg/kg)and benzo(a)pyrene(less than 0.92 mg/kg),which met the requirements of the remediation standard.Therefore,the technology of ISTD showed a great development prospect due to its marking advantages such as fast heating,excellent remediation effect,non-secondary pollution and excavation and transportation.